- You must be logged in to create new topics.
Sarah Davis
Sarah Davis
Forum Replies Created
-
AuthorPosts
-
January 27, 2026 at 3:09 pm in reply to: What does a step up transformer do at a power plant? #332273Sarah DavisMember
Raises generator output voltage to transmission level (110-400 kV+).
Sarah DavisMemberTransformers allow voltage transformation for efficient transmission, grid interconnection, protection coordination, and safe delivery to end users. Without transformers, AC generation could not be economically transmitted over distance.
January 27, 2026 at 6:24 am in reply to: What does the transformer do in a nuclear power plant? #332191Sarah DavisMemberIn a nuclear plant, the transformer system performs the same electrical role as in other thermal plants: GSUs step up generator output to transmission voltage, station service transformers supply turbine-island and balance-of-plant loads, and reserve transformers ensure black-start capability. Reliability requirements are stricter due to safety-critical infrastructure, so monitoring, redundancy, and seismic-rated installation standards are common.
January 26, 2026 at 11:43 pm in reply to: how to determine the power factor of a transformer? #332139Sarah DavisMemberTo determine transformer power factor under load, you measure real power P in kW and apparent power S in kVA at the terminals, then compute power factor as PF = P / S. This can be done using power quality meters or three phase wattmeters with voltage and current transformers. For insulation power factor tests, a different concept is used, where the ratio of resistive to capacitive current in insulation is measured at test voltage. That diagnostic “power factor” indicates dielectric condition rather than load power factor.
January 26, 2026 at 11:22 am in reply to: Why does power loss in transformers increase under load? #332025Sarah DavisMemberAs loading increases, winding resistance losses and stray flux losses scale with I², while cooling systems may reach limits, raising operating temperature and dielectric stress.
January 25, 2026 at 2:49 pm in reply to: What is the power factor of a transformer and why is it important? #331871Sarah DavisMemberTransformer power factor measures the phase angle between voltage and current. A low PF increases current, copper losses, and thermal stress. Utilities monitor PF to optimize loading, reduce losses, and improve capacity utilization.
January 24, 2026 at 7:58 am in reply to: What qualifications are required for power transformer jobs in manufacturing and servicing? #331619Sarah DavisMemberRoles in transformer manufacturing and servicing typically require electrical engineering or electromechanical backgrounds, knowledge of IEC/IEEE standards, oil and dielectric diagnostics (DGA, PD, tan-delta), mechanical assembly, OLTC servicing, and commissioning workflows. Field technicians must understand safety, grounding, lockout/tagout, rigging, and substation procedures.
January 23, 2026 at 8:59 am in reply to: Why are oil-filled power transformers used in substations? #331423Sarah DavisMemberOil filled transformers dominate substation use because they can handle high voltages and large power ratings with efficient cooling and strong insulation. The oil immersion allows compact winding arrangements, high dielectric strength and robust thermal performance, which are critical in grid substations that operate continuously and see fault currents and transients. With radiators, fans or pumps, oil systems support multiple cooling modes. Properly maintained oil insulation provides long service life, and industry standards, monitoring methods and repair practices are well established.
January 23, 2026 at 12:05 am in reply to: What factors contribute to transformer power losses? #331357Sarah DavisMemberLosses include core losses (hysteresis and eddy currents), copper losses in windings, stray losses from leakage fields, and dielectric and mechanical losses. Cooling inefficiencies and OLTC friction also contribute marginally.
January 22, 2026 at 7:12 am in reply to: What does a power transformer specification sheet include? #331189Sarah DavisMemberIt lists kVA/MVA rating, voltage, vector group, impedance, cooling class, BIL, losses, accessories, dimensions, and testing requirements.
January 22, 2026 at 6:24 am in reply to: What does testing of power transformers involve during maintenance cycles? #331177Sarah DavisMemberIt involves insulation tests, winding resistance, ratio, impedance, oil analysis, thermography, OLTC diagnostics, and functional protection checks.
January 22, 2026 at 5:05 am in reply to: What equipment is included in electrical transformers and power equipment? #331159Sarah DavisMemberIt includes transformers, reactors, breakers, switchgear, protection relays, busbars, instrument transformers, surge arresters, and auxiliary control equipment.
January 22, 2026 at 1:42 am in reply to: How does CMM-G filtration protect gearbox components long term? #331111Sarah DavisMemberFiltration at 3 µm and 25 µm removes particles that would otherwise act as abrasives within bearing and gear surfaces. Removing such contaminants prevents accelerated pitting, scuffing, and wear, helping extend gear life and reduce the frequency of expensive repairs or premature replacements.
January 21, 2026 at 8:07 pm in reply to: What are the power inputs and outputs of a transformer? #331029Sarah DavisMemberInput is AC voltage and current at rated frequency; output is transformed AC at new voltage/current level with isolation. kVA is preserved minus losses.
January 21, 2026 at 6:00 pm in reply to: What type of power transformer is used for industrial loads? #330999Sarah DavisMemberIndustrial plants commonly use medium-voltage distribution transformers (e.g., 5-35 kV) or autotransformers for large feeders. Dry-type units are frequent indoors; oil-filled for outdoor/large capacity.
January 21, 2026 at 10:20 am in reply to: What does an image of a power transformer show about cooling systems? #330866Sarah DavisMemberImages reveal radiator banks, fans, oil conservators, cooling ducts, and fin geometries. These details indicate heat dissipation capability, cooling class (ONAN/ONAF/ONAF-ODAF), and transformer rating characteristics.
January 20, 2026 at 7:02 pm in reply to: What factors influence power transformer failure rates in substations? #330647Sarah DavisMemberFailures correlate with overloads, insulation aging, moisture, OLTC wear, bushings defects, contamination, harmonics, lightning/switching surges, and inadequate maintenance.
January 20, 2026 at 11:22 am in reply to: How long does it take to restore power after a transformer blows? #330520Sarah DavisMemberDistribution outages can be restored in hours by switching feeders; full replacement may take days depending on inventory and crew availability.
Sarah DavisMemberABB large power transformers are deployed in transmission substations, grid interconnections, HVDC converter stations, renewable plants, industrial process facilities, and urban substations where compact footprints and advanced cooling/monitoring systems are important. Utilities use them for high reliability and standardized IEC/IEEE compliance.
November 10, 2025 at 10:27 am in reply to: Inquiry about representatives in a specific region and request for two 30 m³ transformer oil storage tanks. #327386Sarah DavisMemberGlobeCore supplies transformer oil storage and handling systems, including tanks, filtration modules, and transfer pumps. We can provide technical drawings, pricing, and delivery schedule.
-
AuthorPosts